Qualification Procedures for making PE 3408 Extra High Molecular Weight YELLOWSTRIPE@ Polyethylene Heat Fusion Joints. BULLETIN NO.106
. Fusion Butt Photographs Fusion Joints. of Qualification Procedures. Fusion Butt Joints 3 4 Correctly made butt fusion joints... Incorrectly made butt fusion joints.. Saddle Photographs Fusion Joints. Saddle of Fusion Joints..5 6,7..8 Correctly made saddle f-usion joints. Incorrectly made saddle fusion joints SocketFusionJoints Photographs of Socket Fusion Joints 9 10, 11...12 " Correctly made socket fusion joints. Incorrectly made socket fusion joints...13 14,15
@ This bulletin is intended to serve as an aid for the training of personnel as qualified installers of PLEXCO YELLOWSTRIPE@ polyethylene pipe in compliance with the regulations of the Department of Transportation, Materials Transportation Bureau, contained in the Code of Federal Regulations Title 49, Part 192. Section 192.285 of these regulations details the procedure to be used to qualify persons to join plastic pipe. As part of this qualification process, the trainee must make sample fusion joints in accordance with the applicable qualified fusion procedure. The resultant fused joints must have the same visual appearance as correctly made fusion joints described and illustrated in this bulletin. In addition, each joint must be cut into at least 3 longitudinal strips, each of which is visually examined and found not to contain voids or discontinuities on the cut surfaces of the joint area; and deformed by bending, torque, or impact such that if failure occurs it does not occur in the joint area. Refer to Bulletin 101 Fusion Procedures for complete fusion procedures. The pictures in this bulletin are of correctly and incorrectly made butt, saddle and socket fusion joints. They are presented to assist the user in evaluating heat fusion joints. PLEXCO YELLOWSTRIPE@ polyethylene pipe and fittings should be joined only by the heat fusion method. DO NOT attempt to join by threading or with solvent cements. If you use compression fittings, instructions for their use should be obtained from the fittings manufacturer. A fusion joint is made in four simple steps" 1.Be sure that the surfaces of the fusion tools, pipe and fittings are free of contaminants prior to use. Inspect polyethylene pipe for cuts, gouges, and deep scratches, and remove these pipe sections before fusing the pipe. 2. Heat the surfaces to be joined -both the pipe and fittings -simultaneously at a prescribed temperature for a specified time. 3. Remove the heater -bring melted surfaces together. 4. Hold until solidified. Before you begin fusing, here are some points to remember. 1. All heater surfaces have q thin layer of non-stick coating that is easily scratched or scraped off. This coating prevents melted PE from adhering firmly to the heater surfaces but occasionally it, too, must be cleaned. Metal tools should NEVER be used to clean the heater surfaces because they scratch and remove the coating. Wood implements and clean, dry, lint-free rags are recommended for cleaning. All-cotton rags are recommended because rags containing a substantial amount of synthetic fibers may melt and char against the heater surface. If the non-stick coating becomes worn or scratched, the heating unit should be recoated. Melted PE may adhere to the heating iron and is more difficult to remove at places where the coating has been scraped off. In addition, since the coating acts as an insulator, heat transfer in these uncoated areas is greater and local overheating can occur. 2. Just before using, wipe heaters to remove dirt and foreign material. Clean heaters as soon as possible after using with wood implements, and clean rags to remove melted or charred plastic. 3. Check the heater temperature with crayon indicators or surface pyrometer at least once a day to make sure the thermometer or other temperature measuring device is reading accurately. Under heavy use conditions, check temperature twice a day. 4. NEVER lay a heating unit on the soil or grass when the heat cycle is completed. Return it to holder, if possible, or at least lay it on a board. Soil will contaminate the joint and is abrasive to the coating; grass may burn and char the heater surface. Important: All fusion equipment must be in proper working order. Consult the manufacturer's operating manual for maintenance and service procedures. Do not use defective equipment.
1. Clean each pipe end with a clean cloth. Place pipe ends into fusion machine. Bring ends together and check alignment. 2. Insert facing unit between pipe ends and lock onto guide rods. Face ends of pipe to the stops. 3. Check alignment of pipe ends. Adjust high-iow if necessary. If adjustment is made, reinsert facing unit and reface to the stops. Always tighten the high side, never loosen the low side. 4. Check heater plate for temperature and wipe surface clean. 5. Insert heater plate between aligned ends and bring ends firmly in contact with plate, but DO NOT APPL y PRESSURE. 6. Heat for times shown below. TABLE 1 -BUTT FUSION TIME CYCLES 7. Remove heater plate after achieving proper melt bead. Quickly observe the parts to be joined to ensure sufficient and uniform melting patterns. Table 2 -Melt Swell Bead Width Guidelines 8. Bring melted ends together quickly. DO NOT SLAM. Apply enough force to roll each bead over to the pipe or fitting surface. Hold this pressure during cooling. 9. Allow the butt fusion to cool, under pressure, for the time shown in Table 1, or about 30 seconds per inch of pipe diameter. 10. DO NOT remove the fused joint from the equipment for an additional three minutes after cooling time. DO NOT test, stress, pull or lay in ground for 10 to 60 minutes after.removal from fusion unit. 11. Clean heater f~ces, being careful not to damage coated surfaces-use wooden implement and clean, dry, lint-free non-synthetic rags. Do not use metal implements to clean heater faces. 12. See Figure 1 for visual parameters of a proper fusion. Guidelines only, exact time depends upon environmental conditions and condition of fusion equipment. Each bead after fusion should have approximately the following diameters: 4
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@ 7 "COLD JOINT" -EXCESSIVE PRESSURE DURING HEAT CYCLE 8 COLD JOINT BREAKS APART 9 MELT BEAD TOO SMALL 11 MELT BEAD TOO LARGE 1 O SMALL BEAD BEND TEST 7
It is recommended that an application tool be used when making saddle fusion joints. Variables in the installation procedure are more easily controlled when a tool is used than when the fusion is made manually. When fusing on a pressurized main, the risk of blow-out can be reduced by using equipment that is in proper working order, following the manufacturer's operating instructions, using recommended fusion procedures and by using relieved-center heater faces when fusing High Volume Tapping Tees. 1. Assemble application unit according to manufacturer's instructions and position on pipe. 2. Remove surface skin from the melt areas of the clean, dry pipe and saddle fitting by roughening with utility cloth (50 to 60 grit). Brush away residue with dry rag after roughening. With experience, the iron can be rocked slightly (about 2% ) and slowly as the melt forms -do not rock excessively as this will enlarge the melt pattern on the pipe. 4. After proper melt time, remove fitting from heater and heater from main with a quick snapping action. Check melt pattern on pipe and fitting -heated surfaces on fitting and pipe should be 100% melted with no cold spots. (A mirror may be used to check the melt on the under surface of the saddle base.) FUSION AND COOLING 5. If melt patterns are satisfactory, press the fitting on the pipe very quickly (within 3 seconds after removing heater) with firm pressure until a melt bead of the following size appears around the entire base of the fitting: HEATING 3. With the heating surfaces of the tool at 5000 :t 10 F place the tool in position on pipe. 8 Force Applied Standard Tapping Tee and Service Saddle HVTT and Branch Saddle Place fitting against heater faces and apply pressure. Heat for time shown in Table 2. TABLE 2- STANDARD TAPPING TEE AND SERVICE SADDLE FUSION TIME CYCLES.Guidelines Only, exact time depends upon environmental conditions and condition of fusion equipment These times apply when using smooth heater faces If serrated heater faces are to be used, reduce heating time by approximately five (5) seconds..use During Heating & Fusion: Heating 60-80 Ibf (All sizes) 120-140 Ibf (All sizes) Fusion & Cooling 40-80 Ibf (All sizes) 2"-60-80 Ibf 3'-80-100 Ibf 4'& 6'-90-120Ibf heat shield on pipe surface for first 15 seconds of this time cycle. Adjust fusion unit to maintain pressure of fitting on pipe. Allow fusion joint to cool for at least the times indicated in Table 2 before releasing pressure. If melt pattern on fitting or pipe is unsatisfactory after heating, apply fitting to pipe and let cool. Remove cutter from tapping tee and cut off fitting top to avoid misuse later. Repeat procedure from Step 1. 6. After letting joint cool 3 minutes beyond that shown in the tables, remove application unit from pipe. Visually check fitting for fusion melt bead around entire fitting base. If fusion joint quality is unacceptable or doubtful, cut off fitting top and apply a new fitting to a new section of pipe. 7. For standard tapping tees and service saddles, let fusion cool an additional 10 minutes prior to pressure testing and tapping the main. Allow an additional 30 minutes before tapping or pressure testing HVTT or branch saddles. 8. Clean heater faces, being careful not to damage coated surfaces -use wooden implement and clean, dry, lint-free non-synthetic rags. Do not use metal implements to clean heater faces. 9. See Figures 12 and 13 for visual parameters of a proper fusion.
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Saddle Fusion Joints -Incorrectly made
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1. Using a pipe cutter, cut off damaged or oval ends of pipe squarely. 2. Use chamfering tool to remove the sharp corner at the pipe end on the outside surface of the pipe. Remove burrs and chips inside pipe ends. 3. To prepare pipe for correct penetration into socket, place depth gauge down flush on end of pipe. 4. Place cold ring clamp around pipe, adjacent to depth gauge. After securing cold ring clamp, remove depth gauge. 5. Fitting surfaces should be clean and dry -wipe with cloth -do not touch with hands. HEATING 6. The socket faces of the heating tool should be at 5000 :t 10 F and clean. 7. First, firmly seat the socket fitting on the male face of the heating tool. Then place the female face on the end of the pipe firmly against the cold ring clamp. Heating time starts when the cold ring clamp is bottomed out on the heater surface. Heat for the prescribed period of time, DO NOT TWIST PIPE, FITTING OR HEATING TOOL. T ABLE 3 -SOCKET FUSION TIME CYCLES 8. Snap the heating tool and fitting from the melted pipe by holding upper part of tool handle with one hand and rapping sharply on the handle with the free hand. Immediately remove fitting from heating tool. 9. Inspect the heated parts quickly to make sure all surfaces have been melted. If melt is not complete, cut off melted pipe end, use a new fitting, and repeat fusion steps 1 through 8. FUSION AND COOLING 10. Within 3 seconds after the heating tool has been removed, firmly push the melted fitting squarely onto the pipe end until it makes firm contact with the cold ring clamp. DO NOT TWIST PIPE OR FITTING. Hold the fitting firmly in place for total cooling time shown in Table 3 to insure proper alignment. After waiting 3 additional minutes cooling time, remove the cold ring clamp and inspect the joint. A good joint will have a uniform melt ring that is flat against the socket and perpendicular to the pipe. There should be no gaps or voids between the fitting and the pipe. 11. Wait an additional 10 minutes to complete cooling before the pipe joint is tested or stressed during burial. 12. See Figure 22 for visual parameters of a proper fusion. 13. Clean heater faces, being careful not to damage coated surfaces-use wooden implement and clean, dry, lint-free non-synthetic rags. Do not use metal implements to clean heater faces. *Guidelines only, exact time depends upon environmental conditions and condition of fusion equipment. 12
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